Compact, high-performance hand-held power tools require optimum cooling of typical heat sources, such as the motor or the electronics, for maximum performance.
The cooling of the hand-held power tool is realized, as a rule, by means of a fan which sits on the motor shaft and sucks cooling air into the housing of the hand-held power tool via air intake openings. In this case, the cooling air is run in as direct a manner as possible past all components which provide the heat sources.
As hand-held power tools are frequently used in rough environments, it is possible that the cooling air may be contaminated with different metal particles, such as, for example, mineral or metallic dusts and fibers. Said particles are sucked in with the cooling air, as a result of which the particles may be deposited in the hand-held power tool, which, in turn, can result in impairment of the hand-held power tool.
DE 10 347 943 A1, as an example, describes a hand-held power tool which comprises a cooling device which comprises, at least in portions thereof, a cooling channel which is closed substantially in relation to an interior of the housing.